U.S. patent application number 13/909487 was filed with the patent office on 2014-10-02 for touchscreen apparatus.
The applicant listed for this patent is Samsung Electro-Mechanics Co., Ltd.. Invention is credited to Moon Suk Jeong, Yong Il KWON, Tah Joon Park.
Application Number | 20140292708 13/909487 |
Document ID | / |
Family ID | 51620313 |
Filed Date | 2014-10-02 |
United States Patent
Application |
20140292708 |
Kind Code |
A1 |
KWON; Yong Il ; et
al. |
October 2, 2014 |
TOUCHSCREEN APPARATUS
Abstract
There is provided a touchscreen apparatus, including a panel
unit including a plurality of driving electrodes extended in a
first axial direction and a plurality of sensing electrodes
extended in a second axial direction intersecting with the first
axial direction, a driving circuit unit applying predetermined
inspection signals to a plurality of driving channels electrically
connected to the plurality of driving electrodes, and an inspecting
unit determining an occurrence of a short between at least one pair
of adjacent driving electrodes among the plurality of driving
electrodes by performing a logical operation on voltages of the
plurality of driving channels.
Inventors: |
KWON; Yong Il; (Suwon,
KR) ; Park; Tah Joon; (Suwon, KR) ; Jeong;
Moon Suk; (Suwon, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Samsung Electro-Mechanics Co., Ltd. |
Suwon |
|
KR |
|
|
Family ID: |
51620313 |
Appl. No.: |
13/909487 |
Filed: |
June 4, 2013 |
Current U.S.
Class: |
345/174 |
Current CPC
Class: |
G06F 3/0416 20130101;
G06F 3/0443 20190501; G06F 3/0445 20190501 |
Class at
Publication: |
345/174 |
International
Class: |
G06F 3/044 20060101
G06F003/044 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 28, 2013 |
KR |
10-2013-0033761 |
Claims
1. A touchscreen apparatus, comprising: a panel unit including a
plurality of driving electrodes extended in a first axial direction
and a plurality of sensing electrodes extended in a second axial
direction intersecting with the first axial direction; a driving
circuit unit applying predetermined inspection signals to a
plurality of driving channels electrically connected to the
plurality of driving electrodes; and an inspecting unit determining
an occurrence of a short between at least one pair of adjacent
driving electrodes among the plurality of driving electrodes by
performing a logical operation on voltages of the plurality of
driving channels.
2. The touchscreen apparatus of claim 1, wherein the inspection
signals have different voltage levels for adjacent driving channels
among the plurality of driving channels.
3. The touchscreen apparatus of claim 1, wherein the inspecting
unit includes: a logical operating unit performing a logical
operation on the voltages measured in adjacent driving channels
among the plurality of driving channels; and a determining unit
determining the occurrence of the short between the at least one
pair of adjacent driving electrodes among the plurality of driving
electrodes according to a signal output from the logical operating
unit.
4. The touchscreen apparatus of claim 3, wherein the logical
operating unit performs an exclusive OR operation on the voltages
measured in the adjacent driving channels.
5. The touchscreen apparatus of claim 4, wherein the determining
unit determines that the short is generated between the at least
one pair of adjacent driving electrodes when the signal output from
the logical operating unit has a low level.
6. A touchscreen apparatus, comprising: a panel unit including a
plurality of driving electrodes extended in a first axial direction
and a plurality of sensing electrodes extended in a second axial
direction intersecting with the first axial direction; a sensing
circuit unit applying predetermined inspection signals to a
plurality of sensing channels electrically connected to the
plurality of sensing electrodes; and an inspecting unit determining
an occurrence of a short between at least one pair of adjacent
sensing electrodes among the plurality of sensing electrodes by
performing a logical operation on voltages of the plurality of
sensing channels.
7. The touchscreen apparatus of claim 6, wherein the inspection
signals have different voltage levels for adjacent sensing channels
among the plurality of sensing channels.
8. The touchscreen apparatus of claim 7, wherein the sensing
circuit unit includes a plurality of integrating circuit units,
each integrating circuit unit including a first switch, a second
switch disposed between the sensing channel and a ground terminal,
an operational amplifier having an inverting terminal connected to
one terminal of the first switch and a non-inverting terminal
connected to a common voltage terminal, and a feedback capacitor
disposed between an output terminal and the inverting terminal of
the operational amplifier, the other terminal of the first switch
included in each of the plurality of integrating circuit units is
connected to each of the plurality of sensing channels, and the
first switch and the second switch of two integrating circuit units
among plurality of integrating circuit units, connected to the
adjacent sensing channels among the plurality of sensing channels,
perform different switching operations.
9. The touchscreen apparatus of claim 6, wherein the inspecting
unit includes: a logical operating unit performing a logical
operation on the voltages measured in adjacent sensing channels
among the plurality of sensing channels; and a determining unit
determining the occurrence of the short between the at least one
pair of adjacent sensing electrodes among the plurality of sensing
electrodes according to signal output from the logical operating
unit.
10. The touchscreen apparatus of claim 9, wherein the logical
operating unit performs an exclusive OR operation on the voltages
measured in the adjacent sensing channels.
11. The touchscreen apparatus of claim 10, wherein the determining
unit determines that the short is generated between the at least
one pair of adjacent sensing electrodes when the signal output from
the logical operating unit has a low level.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the priority of Korean Patent
Application No. 10-2013-0033761 filed on Mar. 28, 2013, in the
Korean Intellectual Property Office, the disclosure of which is
incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a touchscreen
apparatus.
[0004] 2. Description of the Related Art
[0005] In general, a touchscreen apparatus such as a touchscreen, a
touch pad, or the like, an input means attached to a display
apparatus to provide an intuitive input method to a user, has
recently been widely used in various electronic apparatuses such as
cellular phones, personal digital assistants (PDAs), navigation
apparatuses, and the like. Particularly, as the demand for
smartphones has recently increased, the use of a touchscreen
capable of providing various input methods in a limited form factor
has correspondingly increased.
[0006] Touchscreens used in portable apparatuses may mainly be
divided into resistive type touchscreens and capacitive type
touchscreens according to a method of sensing a touch input
implemented therein. Here, the capacitive type touchscreen has
advantages in that it has a relatively long lifespan and various
input methods and gestures may be easily used therewith, such that
the use thereof has increased. Particularly, capacitive type
touchscreens may more easily allow for a multi-touch interface as
compared with resistive type touchscreens, such that they are
widely used in apparatuses such as smartphones, and the like.
[0007] Capacitive type touchscreens include a plurality of
electrodes having a predetermined pattern and defining a plurality
of nodes in which capacitance changes are generated by a touch
input. In the plurality of nodes distributed on a two-dimensional
plane, a self-capacitance or mutual-capacitance change is generated
by the touch input. A coordinate of the touch input may be
calculated by applying a weighted average method, or the like, to
the capacitance change generated in the plurality of nodes.
[0008] However, the plurality of electrodes are arranged to have
significantly narrow micro-gaps therebetween, such that a short may
be generated between adjacent electrodes of the plurality of
electrodes. When a short is generated between the adjacent
electrodes, the touch may not be correctly determined.
[0009] Patent Document 1, which relates to an inspection apparatus
for a touch panel, discloses a method of inspecting a disconnection
and a short in the touch panel using a plurality of capacitive
non-contact type probes and contact type probes scanning interface
terminal units. However, Patent Document 1 does not disclose a
method of inspecting shorts in a touch panel without using an
external inspection apparatus such as the probe.
RELATED ART DOCUMENT
[0010] (Patent Document 1) Korean Patent Laid-Open Publication No.
10-2011-0083196
SUMMARY OF THE INVENTION
[0011] An aspect of the present invention provides a touchscreen
apparatus capable of inspecting whether or not a short has been
generated in a touch panel without using an external inspection
apparatus.
[0012] According to an aspect of the present invention, there is
provided a touchscreen apparatus, including: a panel unit including
a plurality of driving electrodes extended in a first axial
direction and a plurality of sensing electrodes extended in a
second axial direction intersecting with the first axial direction;
a driving circuit unit applying predetermined inspection signals to
a plurality of driving channels electrically connected to the
plurality of driving electrodes; and an inspecting unit determining
an occurrence of a short between at least one pair of adjacent
driving electrodes among the plurality of driving electrodes by
performing a logical operation on voltages of the plurality of
driving channels.
[0013] The inspection signals may have different voltage levels for
adjacent driving channels among the plurality of driving
channels.
[0014] The inspecting unit may include: a logical operating unit
performing a logical operation on the voltages measured in adjacent
driving channels among the plurality of driving channels; and a
determining unit determining the occurrence of the short between
the at least one pair of adjacent driving electrodes among the
plurality of driving electrodes according to a signal output from
the logical operating unit.
[0015] The logical operating unit may perform an exclusive OR
operation on the voltages measured in the adjacent driving
channels.
[0016] The determining unit may determine that the short is
generated between the at least one pair of adjacent driving
electrodes when the signal output from the logical operating unit
has a low level.
[0017] According to another aspect of the present invention, there
is provided a touchscreen apparatus, including: a panel unit
including a plurality of driving electrodes extended in a first
axial direction and a plurality of sensing electrodes extended in a
second axial direction intersecting with the first axial direction;
a sensing circuit unit applying predetermined inspection signals to
a plurality of sensing channels electrically connected to the
plurality of sensing electrodes; and an inspecting unit determining
an occurrence of a short between at least one pair of adjacent
sensing electrodes among the plurality of sensing electrodes by
performing a logical operation on voltages of the plurality of
sensing channels.
[0018] The inspection signals may have different voltage levels for
adjacent sensing channels among the plurality of sensing
channels.
[0019] The sensing circuit unit may include a plurality of
integrating circuit units, each integrating circuit unit including
a first switch, a second switch disposed between the sensing
channel and a ground terminal, an operational amplifier having an
inverting terminal connected to one terminal of the first switch
and a non-inverting terminal connected to a common voltage
terminal, and a feedback capacitor disposed between an output
terminal and the inverting terminal of the operational amplifier,
the other terminal of the first switch included in each of the
plurality of integrating circuit units may be connected to each of
the plurality of sensing channels, and the first switch and the
second switch of two integrating circuit units among plurality of
integrating circuit units, connected to the adjacent sensing
channels among the plurality of sensing channels, may perform
different switching operations.
[0020] The inspecting unit may include: a logical operating unit
performing a logical operation on the voltages measured in adjacent
sensing channels among the plurality of sensing channels; and a
determining unit determining the occurrence of the short between
the at least one pair of adjacent sensing electrodes among the
plurality of sensing electrodes according to signal output from the
logical operating unit.
[0021] The logical operating unit may perform an exclusive OR
operation on the voltages measured in the adjacent sensing
channels.
[0022] The determining unit may determine that the short is
generated between the at least one pair of adjacent sensing
electrodes when the signal output from the logical operating unit
has a low level.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The above and other aspects, features and other advantages
of the present invention will be more clearly understood from the
following detailed description taken in conjunction with the
accompanying drawings, in which:
[0024] FIG. 1 is a perspective view showing the exterior of an
electronic apparatus including a touchscreen apparatus according to
an embodiment of the present invention;
[0025] FIG. 2 is a view showing a panel unit capable of being
included in the touchscreen apparatus according to the embodiment
of the present invention;
[0026] FIG. 3 is a view showing a cross-section of the panel unit
shown in FIG. 2;
[0027] FIG. 4 is a view showing a touchscreen apparatus according
to an embodiment of the present invention;
[0028] FIG. 5 is a view showing the touchscreen apparatus for
inspecting whether or not a short is generated between a plurality
of first electrodes according to the embodiment of the present
invention; and
[0029] FIG. 6 is a view showing the touchscreen apparatus for
inspecting whether or not a short is generated between a plurality
of second electrodes according to the embodiment of the present
invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0030] Hereinafter, embodiments of the present invention will be
described in detail with reference to the accompanying drawings.
The invention may, however, be embodied in many different forms and
should not be construed as being limited to the embodiments set
forth herein. Rather, these embodiments are provided so that this
disclosure will be thorough and complete, and will fully convey the
scope of the invention to those skilled in the art. In the
drawings, the shapes and dimensions of elements may be exaggerated
for clarity, and the same reference numerals will be used
throughout to designate the same or like elements.
[0031] FIG. 1 is a perspective view showing the exterior of an
electronic apparatus including a touchscreen apparatus according to
an embodiment of the present invention.
[0032] Referring to FIG. 1, an electronic apparatus 100 according
to the present embodiment may include a display apparatus 110 for
outputting a screen therethrough, an input unit 120, an audio unit
130 for outputting a sound, and the like, and may be integrated
with the display apparatus 110 to provide a touchscreen
apparatus.
[0033] As shown in FIG. 1, in general, a mobile apparatus may be
configured in such a manner that a touchscreen apparatus is
integrated with a display apparatus, and the touchscreen apparatus
may have a high degree of light transmissivity to which an image
passes through a screen displayed on the display apparatus. Thus,
the touchscreen apparatus may be manufactured by forming an
electrode on abase substrate formed of a transparent film material
such as polyethylene terephthalate (PET), polycarbonate (PC),
polyethersulfone (PES), polyimide (PI) or the like, the electrode
being formed of an electrically conductive transparent material
such as indium-tin oxide (ITO), indium zinc oxide (IZO), zinc oxide
(ZnO), carbon nanotubes (CNT) or graphene. A wiring pattern
connected to the electrode formed of a transparent conductive
material is formed in a bezel region of the display apparatus.
Since the wiring pattern is visually shielded by the bezel region,
the wiring pattern may also be formed of a metal such as silver
(Ag), copper (Cu), or the like.
[0034] The touchscreen apparatus according to an embodiment of the
present invention may be a capacitive type touchscreen apparatus
and accordingly, it may include a plurality of electrodes having a
predetermined pattern. Also, the touchscreen apparatus according to
an embodiment of the present invention may include a capacitance
detection circuit detecting changes in capacitance generated in the
plurality of electrodes, an analog-to-digital conversion circuit
converting an output signal from the capacitance detection circuit
into a digital value, an operation circuit determining a touch
input by using data converted as the digital value, and the
like.
[0035] FIG. 2 is a view showing a panel unit capable of being
included in the touchscreen apparatus according to the embodiment
of the present invention.
[0036] Referring to FIG. 2, a panel unit 200 according to the
present embodiment includes a substrate 210 and a plurality of
electrodes 220 and 230 provided on the substrate 210. Although not
shown in FIG. 2, the plurality of electrodes 220 and 230 may be
respectively electrically connected with wiring patterns of a
circuit board, which is bonded to one end of the substrate 210,
through wirings and bonding pads. A controller integrated circuit
is mounted on the circuit board to detect a sensing signal
generated from the plurality of electrodes 220 and 230 and
determine a touch input from the sensing signal.
[0037] In the case of the touchscreen apparatus, the substrate 210
may be a transparent substrate on which the plurality of electrodes
220 and 230 are formed, and may be formed of a plastic material
such as polyimide (PI), polymethylmethacrylate (PMMA),
polyethyleneterephthalate (PET), or polycarbonate (PC), or tempered
glass. Further, with respect to a region in which the wirings
connected to the plurality of electrodes 220 and 230 are formed,
except for a region in which the plurality of electrodes 220 and
230 are formed, a predetermined printing region may be formed on
the substrate 210 in order to visually shield the wirings generally
formed of an opaque metal material.
[0038] The plurality of electrodes 220 and 230 may be provided on
one surface or both surfaces of the substrate 210. The touchscreen
apparatus may be formed of indium tin-oxide (ITO), indium
zinc-oxide (IZO), zinc oxide (ZnO), carbon nano tube (CNT), a
graphene based material, or the like, having transparency and
conductivity. In FIG. 2, the plurality of electrodes 220 and 230
having a diamond-like pattern are illustrated, but the present
invention is not limited thereto and the electrodes 220 and 230 may
have various polygonal patterns such as a rectangular pattern, a
triangular pattern, or the like.
[0039] The plurality of electrodes 220 and 230 include the first
electrodes 220 extending in an X-axis direction and the second
electrodes 230 extending in a Y-axis direction. The first
electrodes 220 and the second electrodes 230 may intersect each
other on both surfaces of the substrate 210, or on different
substrates 210. In the case in which the first electrodes 220 and
the second electrodes 230 are all formed on one surface of the
substrate 210, predetermined insulating layers may be partially
formed in intersections between the first electrodes 220 and the
second electrodes 230.
[0040] The touchscreen apparatus, electrically connected to the
plurality of electrodes 220 and 230 to sense a touch input, may
detect changes in capacitance generated from the plurality of
electrodes 220 and 230 according to a touch input applied thereto
and sense the touch input therefrom. The first electrodes 220 may
be connected to channels defined as D1 to D8 in the controller
integrated circuit to thereby receive predetermined driving
signals, and the second electrodes 230 may be connected to channels
defined as S1 to S8 to thereby be used for the touchscreen
apparatus to detect a sensing signal. Here, the controller
integrated circuit may detect, as a sensing signal, changes in
mutual-capacitance generated between the first electrodes 220 and
the second electrodes 230, and may be operated in such a manner
that driving signals are sequentially applied to the respective
first electrodes 220 and the changes in capacitance are
simultaneously detected by the second electrodes 230.
[0041] FIG. 3 is a view showing a cross-section of the panel unit
shown in FIG. 2. FIG. 3 is a cross-sectional view of the panel unit
200 illustrated in FIG. 2, taken along Y-Z plane, and the panel
unit 200 may include a substrate 310 and a plurality of electrodes
320 and 330 as described above with reference to FIG. 2 and further
include a cover lens 340 receiving contact. The cover lens 340 may
be disposed on the second electrode 330 used for detecting a
sensing signal and receive a touch input from a contact object 350
such as a finger, or the like.
[0042] When driving signals are sequentially applied to the first
electrodes 320 through the channel D1 to D8, mutual capacitance may
be generated between the first electrodes 320 to which the driving
signals are applied and the second electrode 330. When the driving
signals are sequentially applied to the first electrodes 320,
changes in mutual capacitance generated between the first
electrodes 320 and the second electrode 330 adjacent to a region
with which the contact object 350 is brought into contact may be
caused. The changes in capacitance may be proportional to the area
of an overlapping region between the contact object 350 and the
first electrodes 320 to which the driving signals are applied and
the second electrode 330. In FIG. 3, mutual capacitance generated
between the first electrodes 320 and the second electrode 330
connected to the channels D2 and D3 is affected by the contact
object 350.
[0043] FIG. 4 is a view showing a touchscreen apparatus according
to an embodiment of the present invention. Referring to FIG. 4, the
touchscreen apparatus according to the present embodiment may
include a panel unit 410, a driving circuit unit 420, a sensing
circuit unit 430, a signal converting unit 440, an operating unit
450, and an inspecting unit 460.
[0044] The panel unit 410 may include a plurality of first
electrodes X1 to Xm extended in a first axial direction, that is, a
horizontal direction of FIG. 4 and a plurality of second electrodes
Y1 to Yn extended in a second axial direction, that is, a vertical
direction of FIG. 4, intersecting with the first axial direction.
Changes in capacitance C11 to Cmn are generated in intersections
between the first electrodes X1 to Xm and the second electrodes Y1
to Yn. The changes in capacitance C11 to Cmn generated in the
intersections between the first electrodes X1 to Xm and the second
electrodes Y1 to Yn may be changes in mutual capacitance generated
by driving signals applied to the first electrodes X1 to Xm by the
driving circuit unit 420. Meanwhile, the driving circuit unit 420,
the sensing circuit unit 430, the signal converting unit 440, the
operating unit 450, and the inspecting unit 460 may be implemented
as a single integrated circuit (IC).
[0045] The driving circuit unit 420 may apply predetermined driving
signals to the first electrodes X1 to Xm of the panel unit 410
through driving channels D1 to Dm. The driving signals may be
square wave signals, sine wave signals, triangle wave signals, or
the like, having a predetermined period and amplitude and be
sequentially applied to each of the plurality of first electrodes
X1 to Xm. Although the case in which circuits for generating and
applying the driving signals are individually connected to the
plurality of first electrodes X1 to Xm is shown in FIG. 4, a single
driving signal generating circuit may also generate driving signals
and apply the generated driving signals to the plurality of first
electrodes X1 to Xm, respectively, using a switching circuit. The
plurality of first electrodes X1 to Xm may be referred to as a
plurality of driving electrodes.
[0046] The sensing circuit unit 430 may include an integrating
circuit for sensing the changes in capacitance C11 to Cmn generated
in a plurality of nodes, and the integrating circuit may be
connected to the plurality of second electrodes Y1 to Yn through
sensing channels S1 to Sn. The integrating circuit may include at
least one operational amplifier and a capacitor C1 having a
predetermined degree of capacitance, and in this case, the
operational amplifier has an inverting input terminal connected to
the second electrodes Y1 to Yn to convert the changes in
capacitance C11 to Cmn into analog signals such as voltage signals,
or the like, and then output the analog signals. A detailed
configuration of the integrating circuit included in the sensing
circuit unit 430 will be described below. In the case in which the
driving signals are sequentially applied to the plurality of first
electrodes X1 to Xm, respectively, since the changes in capacitance
may be simultaneously detected in the plurality of second
electrodes Y1 to Yn, the number of integrating circuits may
correspond to the number (n) of second electrodes Y1 to Yn. The
plurality of second electrodes Y1 to Yn may be referred to as a
plurality of sensing electrodes.
[0047] The signal converting unit 440 may generate a digital signal
S.sub.D from an analog signal generated by the integrating circuit.
As an example, the signal converting unit 440 may include a
time-to-digital converter (TDC) circuit for measuring a period of
time for which an analog signal in a voltage form output from the
sensing circuit unit 430 reaches a predetermined reference voltage
level and converting the period of time into the digital signal
S.sub.D or an analog-to-digital converter (ADC) circuit for
measuring an amount by which a level of the voltage output from the
sensing circuit unit 430 is changed for a predetermined period of
time and converting the amount into the digital signal S.sub.D.
[0048] The operating unit 450 may determine a touch input applied
to the panel unit 410 using the digital signal S.sub.D. As an
example, the operating unit 450 may determine the number of touch
inputs applied to the panel unit 410, coordinates of the touch
input, a gesture based on the touch input, or the like. The digital
signal S.sub.D basically used in determining the touch input by the
operating unit 450 may be data digitizing the changes in
capacitance C11 to Cmn, and particularly, may be data representing
a difference in capacitance between a case in which the touch input
is not generated and a case in which the touch input is generated.
Typically, in a capacitive type touchscreen apparatus, it may be
appreciated that the region with which a conductive object comes
into contact has a lower level of capacitance than the region in
which the contact is not generated.
[0049] The inspecting unit 460 may inspect whether or not a short
is generated between the adjacent first electrodes among the
plurality of first electrodes X1 to Xm of the panel unit or whether
or not the short is generated between the adjacent second
electrodes among the plurality of second electrodes Y1 to Yn. The
inspecting unit 460 may be electrically connected to a plurality of
channels connected to the plurality of first electrodes X1 to Xm
and the plurality of second electrodes Y1 to Yn, respectively, to
measure voltages of the plurality of channels and logically operate
the measured voltages, thereby determining whether or not the short
is generated. A detailed configuration of the inspecting unit 460
may be provided with reference to FIGS. 5 and 6, and the
touchscreen apparatus of FIG. 4 will be described in more detail
with reference to FIGS. 5 and 6.
[0050] FIG. 5 is a view showing the touchscreen apparatus for
inspecting whether or not a short is generated between a plurality
of first electrodes according to the embodiment of the present
invention. In FIG. 5, a portion of the touchscreen apparatus
illustrated in FIG. 4, in which whether or not a short is generated
between a plurality of first electrodes is inspected, may be shown
in detail, while the same portions thereof as those of FIG. 4 are
briefly represented or omitted.
[0051] Referring to FIG. 5, the touchscreen apparatus according to
the embodiment of the present invention may include the panel unit
410, the driving circuit unit 420, and the inspecting unit 460. The
panel unit 410, the driving circuit unit 420, and the inspecting
unit 460 of FIG. 5 are the same components as the panel unit 410,
the driving circuit unit 420, and the inspecting unit 460 of FIG.
4. Therefore, differences between the components will be mainly
described. FIG. 5 shows the panel unit 410 in which the plurality
of second electrodes of the panel unit 410 illustrated in FIG. 4
are omitted and shows only four first electrodes X1 to X4 for
convenience of explanation.
[0052] In the case in which the touchscreen apparatus according to
the embodiment of the present invention inspects whether or not a
short is generated between the plurality of first electrodes, the
inspecting unit 460 measures voltages of a plurality of driving
channels D1 to D4 electrically connected to a plurality of first
electrodes X1 to X4. Although not shown in FIG. 5, since the
plurality of driving channels D1 to D4 may be electrically
connected to the plurality of first electrodes X1 to X4 through
bonding pads and wirings, voltages of the plurality of respective
first electrodes X1 to X4 may be maintained in the same levels as
those of the plurality of driving channels D1 to D4. Therefore, the
inspecting unit 460 may measure voltages of the plurality of first
electrodes X1 to X4 by measuring voltages of the plurality of
driving channels D1 to D4.
[0053] In this case, in order for the inspecting unit 460 to
determine whether or not a short is generated between the plurality
of first electrodes, the driving circuit unit 420 applies signals
having different voltage levels, that is, inspection signals to
adjacent driving channels. For example, in the case in which a high
level voltage is applied to an even numbered channel, a low level
voltage may be applied to an odd numbered channel. In addition, on
the other hand, in the case in which the low level voltage is
applied to the even numbered channel, the high level voltage may be
applied to the odd numbered channel. Although not shown in FIG. 5,
it is assumed that the sensing circuit unit 430 of FIG. 4 is not
operated when it is determined whether or not a short is generated
between the plurality of first electrodes.
[0054] In the case in which the short is generated between the
plurality of first electrodes X1 to X4, voltage levels of the
adjacent first electrodes between which the short is generated are
the same and in this case, the inspecting unit 460 may inspect
whether or not the short is generated between the plurality of
first electrodes X1 to X4 by performing a logical operation on
voltages of the adjacent first electrodes. The inspecting unit 460
may include a logical operating unit 461 and a determining unit
462. The logical operating unit 461 may include logic gates XOR1 to
XOR3 to perform an exclusive OR operation on the voltages measured
in the plurality of driving channels adjacent to each other, and
the determining unit 462 may determine the occurrence of a short
that may be generated between the adjacent first electrodes of the
plurality first electrodes X1 to X4 from signals output from the
logic gates XOR1 to XOR3.
[0055] For example, the description is made on the assumption that
the driving circuit unit 420 applies the high level voltage to the
odd numbered channel and applies the low level voltage to the even
numbered channel. In the case in which the short is not generated
between the first electrodes, the logical gates XOR1 to XOR3
respectively output high level signals and the determining unit 462
determines that the short is not generated between the first
electrodes X1 to X4, from the signals output from the logical gates
XOR1 to XOR3.
[0056] On the other hand, in the case in which the short is
generated between the first electrode X2 and the first electrode X3
among the first electrodes X1 to X4, since a high level voltage is
measured in the channel D1 while low level voltages are measured in
the channels D2 to D4, the logical gate XOR1 outputs a high signal
and the logical gates XOR2 and XOR3 output low signals. The
determining unit 462 may determine that a short has been generated
between at least one pair of adjacent electrodes among the first
electrodes X2 to X4, from the low signals output from the logic
gates XOR2 and XOR3.
[0057] FIG. 6 is a view showing the touchscreen apparatus for
inspecting whether or not a short is generated between a plurality
of second electrodes according to the embodiment of the present
invention. In FIG. 6, a portion of the touchscreen apparatus
illustrated in FIG. 4, in which whether or not a short is generated
between a plurality of second electrodes is inspected, may be shown
in detail, while the same portions thereof as those of FIG. 4 are
briefly represented or omitted.
[0058] Referring to FIG. 6, the touchscreen apparatus according to
the embodiment of the present invention may include the panel unit
410, the driving circuit unit 430, and the inspecting unit 460. The
panel unit 410, the sensing circuit unit 430, and the inspecting
unit 460 of FIG. 6 are the same components as the panel unit 410,
the sensing circuit unit 430, and the inspecting unit 460 of FIG.
4. Therefore, differences between the components will be mainly
described. FIG. 6 shows the panel unit 410 in which the plurality
of first electrodes of the panel unit 410 illustrated in FIG. 4 are
omitted and shows only four second electrodes Y1 to Y4 for
convenience of explanation.
[0059] As shown in FIG. 6, the sensing circuit unit 430 may include
a plurality of integrating circuit units 431 to 434, each
integrating circuit unit including a first switch SW1 having the
other terminal connected to a sensing channel, a second switch SW2
disposed between the sensing channel and a ground terminal, an
operational amplifier OPA having an inverting terminal connected to
one terminal of the first switch SW1 and a non-inverting terminal
connected to a common voltage (VCM) terminal, and a feedback
capacitor CF disposed between an output terminal and the inverting
terminal of the operational amplifier OPA. The integrating circuit
units 431 to 434 may respectively receive charges stored in node
capacitors formed in intersections between the plurality of first
electrodes and the plurality of second electrodes Y1 to Y4 and then
integrate the received charges in the operational amplifier OPA and
the feedback capacitor CF, thereby detecting the changes in
capacitance that may be generated in the node capacitors. The
analog signal generated from each of the integrating circuit units
431 to 434 may be transferred to the signal converting unit 440 of
FIG. 4 as described above.
[0060] In the case in which the touchscreen apparatus according to
the embodiment of the present invention inspects whether or not a
short is generated between the plurality of second electrodes, the
inspecting unit 460 measures voltages of a plurality of sensing
channels S1 to S4 electrically connected to a plurality of second
electrodes Y1 to Y4. Although not shown in FIG. 6, since the
plurality of sensing channels S1 to S4 may be electrically
connected to the plurality of second electrodes Y1 to Y4 through
bonding pads and wirings, voltages of the plurality of second
electrodes Y1 to Y4 may be maintained in the same levels as those
of the plurality of sensing channels S1 to S4. Therefore, the
inspecting unit 630 may measure the voltages of the plurality of
second electrodes Y1 to Y4 by measuring voltages of the plurality
of sensing channels S1 to S4.
[0061] In this case, the sensing circuit unit 430 provides
predetermined inspection signals to the adjacent sensing channels
in order to apply different level voltages to the adjacent sensing
channels. To this end, the first switch and the second switch of
two integrating circuit units connected to the adjacent sensing
channels perform different switching operations. For example, in
the case in which a high level voltage is applied to the odd
numbered channel and a low level voltage is applied to the even
numbered channel, the switches SW1 of the integrating circuit units
431 and 433 are switched on and the switches SW2 thereof are
switched off, and the switches SW1 of the integrating circuit units
432 and 434 are switched off and the switches SW2 thereof are
switched on. On contrary to this, in the case in which a low level
voltage is applied to the odd numbered channel and a high level
voltage is applied to the even numbered channel, the switches SW2
of the integrating circuit units 431 and 433 are switched on and
the switches SW1 are switched off, and the switches SW2 of the
integrating circuit units 432 and 434 are switched off and the
switches SW1 thereof are switched on. In this case, it is assumed
that the level of the common voltage (VCM) is a level that could be
recognized by the logic gates XOR4 to XOR6 as the high level
voltage. In addition, although not shown in FIG. 6, it is assumed
that the driving circuit unit 420 of FIG. 4 maintains all of the
plurality of first electrodes at the same potential.
[0062] In the case in which the short is generated between the
plurality of second electrodes Y1 to Y4, voltage levels of the
adjacent second electrodes between which the short is generated are
the same and in this case, the inspecting unit 460 may inspect
whether or not the short is generated between the plurality of
second electrodes Y1 to Y4 by performing a logical operation on
voltages of the adjacent second electrodes. The inspecting unit 460
may include the logical operating unit 461 and the determining unit
462. The logical operating unit 461 may include logic gates XOR4 to
XOR6 to perform an exclusive OR operation on the voltages measured
in the plurality of driving channels adjacent to each other, and
the determining unit 462 may determine the occurrence of a short
that may be generated between the adjacent second electrodes of the
plurality second electrodes Y1 to Y4 from signals output from the
logic gates XOR4 to XOR6.
[0063] For example, the description is made on the assumption that
a high level signal is applied to the odd numbered channel and a
low level signal is applied to the even numbered channel. In the
case in which the short is not generated between the second
electrodes, the logical gates XOR4 to XOR6 respectively output high
level signals and the determining unit 462 determines that the
short is not generated between the second electrodes Y1 to Y4, from
the signals output from the logical gates XOR4 to XOR6.
[0064] On the other hand, in the case in which the short is
generated between the second electrode Y2 and the second electrode
Y3 among the second electrodes Y1 to Y4, since a high level voltage
is measured in the channel S1 while a low level voltage is measured
in the channels S2 to S4, the logical gate XOR4 outputs a high
signal and the logical gates XOR5 and XOR6 output low signals. The
determining unit 462 may determine that a short has been generated
between at least one pair of adjacent electrodes among the second
electrodes Y2 to Y4, from the low signals output from the logic
gates XOR5 and XOR6.
[0065] As set forth above, in the case of the touchscreen apparatus
according to the embodiments of the present invention, whether or
not a short is generated in a touch panel can be inspected using a
simple method without an external inspection apparatus to decrease
costs required for inspecting the touch panel.
[0066] While the present invention has been shown and described in
connection with the embodiments, it will be apparent to those
skilled in the art that modifications and variations can be made
without departing from the spirit and scope of the invention as
defined by the appended claims.
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